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Across tropical ecosystems, global environmental change is causing drier climatic conditions and increased nutrient deposition. Such changes represent large uncertainties due to unknown interactions between drought and nutrient availability in controlling ecosystem net primary productivity (NPP). Using a large-scale manipulative experiment, we studied for 4 years whether nutrient availability affects the individual and integrated responses of aboveground and belowground ecosystem processes to throughfall exclusion in 30-year-old mixed plantations of tropical dry forest tree species in Guanacaste, Costa Rica. We used a factorial design with four treatments: control, fertilization (F), drought (D), and drought + fertilization (D + F). While we found that a 13 %–15 % reduction in soil moisture only led to weak effects in the studied ecosystem processes, NPP increased as a function of F and D + F. The relative contribution of each biomass flux to NPP varied depending on the treatment, with woody biomass being more important for F and root biomass for D + F and D. Moreover, the F treatment showed modest increases in maximum canopy cover. Plant functional type (i.e., N fixation or deciduousness) and not the experimental manipulations was the main source of variation in tree growth. Belowground processes also responded to experimental treatments, as we found a decrease in nodulation for F plots and an increase in microbial carbon use efficiency for F and D plots. Our results emphasize that nutrient availability, more so than modest reductions in soil moisture, limits ecosystem processes in tropical dry forests and that soil fertility interactions with other aspects of drought intensity (e.g., vapor pressure deficit) are yet to be explored.

Simultaneous oxidation and nitrocarburizing of AISI 316 SS at 580 °C for 5, 10, 15, and 20 min were studied using self-protecting pastes of sodium cyanate and sodium carbonate. The analytical techniques of XRD and SEM/EDS allowed the characterization of surface modifications. The corrosion resistance was evaluated in a synthetic seawater solution using the cyclic potentiodynamic polarization technique. The cross-section hardness and wear resistance were assessed by Vickers indentation and pin-on-disc, respectively. This thermochemical process formed an oxidized compound layer above a solid nitrogen solution in austenite. The compound layer was composed of intermixed crystals of Fe3O4, ε-Fe3N, and expanded austenite. With increasing relative proportions of the first two phases and decreasing relative proportions of the third phase with increasing treatment time. The balance between the expanded austenite and the chemical composition of the compound layer improved the hardness, the wear-resistant, and the pitting corrosion resistance of the AISI 316L SS surface simultaneously. Oxy-nitrocarburizing at 580 °C for 10 min allowed the best-localized corrosion resistance. However, the sample oxy-nitrocarburized for 20 min reached a more stable passive zone with the highest wear resistance. Self-protective pastes based on sodium cyanates and carbonates allowed the oxy-nitrocarburizing process to consume less salt than the traditional molten salts.

Introduction and objectives: Cirrhosis and diabetes mellitus are two chronic diseases with a significant impact on quality of life glucose intolerance has been observed in about 80% of patients with cirrhosis, 30-60% of patients with advanced cirrhosis develop diabetes. The development of diabetes as a complication of cirrhosis is referred to as hepatogenic diabetes and type 2 diabetes which the patient develops prior to the presence of cirrhosis. Hepatogenic diabetes, unlike diabetes mellitus, lacks a family history, less obesity, and a lower incidence of micro and macrovascular complications. Diabetes increases morbidity and mortality in patients with liver cirrhosis. The effect of type 2 diabetes and hepathogenic diabetes on the clinical outcome of cirrhosis has been evaluated in a few studies. Diabetes mellitus has been shown to be associated with an increased risk of complications and mortality. We consider it important to assess the association between the type of diabetes (hepatogenic and non-hepatogenic) with the presence of decompensation of cirrhosis (hemorrhage, hepatic encephalopathy, ascites, spontaneous bacterial peritonitis). Material and methods: Ambispective, observational, descriptive study. Patients with a diagnosis of liver cirrhosis and diabetes from an outpatient clinic at the General Hospital of Ticomán and a review of the clinical record are included, collecting information on decompensation events (hemorrhage, hepatic encephalopathy, spontaneous bacterial peritonitis, ascites). Descriptive analysis is performed of the variables. Results: Twenty-eight patients were included, of whom 15 suffer from type 2 diabetes mellitus and 13 of them were diagnosed with hepatogenic diabetes. Hepatogenic diabetes was diagnosed in 9 patients with impaired fasting glucose levels and in 4 patients with a glucose tolerance curve. In both groups, the male gender predominated (53.3 and 61% respectively), the main etiology of alcohol cirrhosis. In the group with hepatogenic diabetes, 76.92% presented some decompensation event, the most frequent being upper gastrointestinal bleeding in 80%. In this group of patients, they correspond to Child A 53.84%, Child B 38.46 and Child C 7.69%. 76.92% of the patients had a portal diameter greater than 10mm, 61.53% of the patients had large esophageal varices. In 53.84% of the patients, they were difficult to control, receiving treatment with a combination of insulin and metformin. On the other hand, in the group of patients with diabetes mellitus 69.23% presented decompensation, the most common hemorrhage in 46.66%, of these patients 33.3% Child A, 53.33% Child B and 13.33% Child C. 53.33% had a diameter of the portal greater than 10mm and 61.53 large esophageal varices. 33.33% of the patients were difficult to manage, being treated with combinations of insulin, metformin and linagliptin. Discussion: The association of diabetes with decompensation events has been observed in some studies, Del Vecchio et al. found that diabetes was more frequent in subjects with decompensation than in those with compensated cirrhosis, with a prevalence of 63%. Targest et al. Diabetes is commonly associated with a significant increase in the development of spontaneous bacterial peritonitis. Goh et al. Diabetes is associated with an increased risk of mortality in patients with cirrhosis. Conclusions: In our study, we observed that decompensation events were more common in the group of patients with hepatogenic cirrhosis, being the main gastrointestinal bleeding, in addition to presenting a larger diameter of the portal vein on ultrasound and a higher percentage of large esophageal varices. And we observed this group of patients presented difficult management of glucose levels being treated with combinations of insulin and metformin.The authors declare that there is no conflict of interest.

Introduction and aims: The aim of the present study was to evaluate the feasibility of endoscopic submucosal dissection (ESD) and determine the clinical and pathologic characteristics of early gastric cancers and premalignant lesions treated with that technique at the Hospital Nacional of the Department of Health and a private clinic in Lima, Peru. Materials and methods: A descriptive study of all pre-malignant and malignant gastric lesions treated with ESD at the Gastroenterology Service of the Hospital Arzobispo Loayza and the Clínica Angloamericana was conducted within the time frame of January 2012 and January 2017. Results: A total of 13 lesions were resected through ESD: 8 adenocarcinomas (61.53%), 3 adeno-mas with high-grade dysplasia (23%), and 2 adenomas with low-grade dysplasia (15.38%). Twelve lesions (92.3%) were located in the lower third of the stomach. Slightly elevated lesions (Paris classification IIa) (4 lesions, 30.76%) and mixed slightly elevated lesions with a depressed component (IIa + IIc) (4 lesions, 30.76%) predominated. The mean size of the resected specimens was 35 mm. Complete resection of all lesions was achieved in 11 cases (84.6%) and en bloc resection was carried out in 11 cases (84.6%). Resection was curative in 6 cases (75%), from the total of 8 resected adenocarcinomas. One case of perforation was the only complication reported (7.6%) and it was surgically resolved. Conclusions: The feasibility and efficacy of ESD for the treatment of early gastric cancer was demonstrated at two healthcare centers in Lima, Peru. The complication rate was similar to that reported in the international medical literature. Resumen: Introducción y objetivos: El objetivo del estudio fue evaluar la factibilidad de la disección endoscópica submucosa (DES) y determinar las características clínico-patológicas de los cánceres gástricos tempranos y lesiones premalignas tratados con esta técnica en un Hospital Nacional del Ministerio de Salud y en una clínica particular en Lima, Perú. Materiales y métodos: Estudio descriptivo de todas las lesiones gástricas malignas y premalignas tratadas con DES en el Servicio de Gastroenterología del Hospital Arzobispo Loayza y la Clínica Angloamericana desde enero de 2012 a enero de 2017. Resultados: Se resecaron un total de 13 lesiones con DES: 8 adenocarcinomas (61.53%), 3 adenomas con displasia de alto grado (23%) y 2 adenomas con displasia de bajo grado (15.38%). Doce lesiones (92.3%) se localizaron en el tercio inferior gástrico. Predominaron las lesiones plano elevadas (IIa de París; 4 lesiones, 30.76%) y las mixtas plano elevadas con componente deprimido (IIa + IIc; 4 lesiones, 30.76%). La media de tamaño del espécimen resecado fue de 35 mm. Se consiguió resección completa, del total de lesiones, en 11 casos (84.6%), y resección en bloque en 11 casos (84.6%). En 6 casos (75%), de un total de 8 adenocarcinomas resecados, se observó una resección curativa. Se reportó una complicación (7.6%) la cual fue perforación y se resolvió por cirugía. Conclusiones: En 2 centros de Lima, Perú, se demostró la factibilidad y eficacia de la DES para el tratamiento del cáncer gástrico precoz, con una tasa de complicaciones similar a la descrita en la literatura internacional. Keywords: Gastric cancer, Submucosal endoscopic dissection, Palabras clave: Cáncer gástrico, Disección endoscópica submucosa

Resumen: Introducción y objetivos: El objetivo del estudio fue evaluar la factibilidad de la disección endoscópica submucosa (DES) y determinar las características clínico-patológicas de los cánceres gástricos tempranos y lesiones premalignas tratados con esta técnica en un Hospital Nacional del Ministerio de Salud y en una clínica particular en Lima, Perú. Material y métodos: Estudio descriptivo de todas las lesiones gástricas malignas y premalignas tratadas con DES en el Servicio de Gastroenterología del Hospital Arzobispo Loayza y la Clínica Angloamericana desde enero de 2012 a enero de 2017. Resultados: Se resecaron un total de 13 lesiones con DES: 8 adenocarcinomas (61.53%), 3 adenomas con displasia de alto grado (23%) y 2 adenomas con displasia de bajo grado (15.38%). Doce lesiones (92.3%) se localizaron en el tercio inferior gástrico. Predominaron las lesiones plano elevadas (IIa de París; 4 lesiones, 30.76%) y las mixtas plano elevadas con componente deprimido (IIa + IIc; 4 lesiones, 30.76%). La media de tamaño del espécimen resecado fue de 35 mm. Se consiguió resección completa, del total de lesiones, en 11 casos (84.6%), y resección en bloque en 11 casos (84.6%). En 6 casos (75%), de un total de 8 adenocarcinomas resecados, se observó una resección curativa. Se reportó una complicación (7.6%) la cual fue perforación y se resolvió por cirugía. Conclusiones: En 2 centros de Lima, Perú, se demostró la factibilidad y eficacia de la DES para el tratamiento del cáncer gástrico precoz, con una tasa de complicaciones similar a la descrita en la literatura internacional. Abstract: Introduction and aims: The aim of the present study was to evaluate the feasibility of endoscopic submucosal dissection (ESD) and determine the clinical and pathologic characteristics of early gastric cancers and premalignant lesions treated with that technique at the Hospital Nacional of the Department of Health and a private clinic in Lima, Peru. Material and methods: A descriptive study of all pre-malignant and malignant gastric lesions treated with ESD at the Gastroenterology Service of the Hospital Arzobispo Loayza and the Clínica Angloamericana was conducted within the time frame of January 2012 and January 2017. Results: A total of 13 lesions were resected through ESD: 8 adenocarcinomas (61.53%), 3 adenomas with high-grade dysplasia (23%), and 2 adenomas with low-grade dysplasia (15.38%). Twelve lesions (92.3%) were located in the lower third of the stomach. Slightly elevated lesions (Paris classification IIa) (4 lesions, 30.76%) and mixed slightly elevated lesions with a depressed component (IIa + IIc) (4 lesions, 30.76%) predominated. The mean size of the resected specimens was 35 mm. Complete resection of all lesions was achieved in 11 cases (84.6%) and en bloc resection was carried out in 11 cases (84.6%). Resection was curative in 6 cases (75%), from the total of 8 resected adenocarcinomas. One case of perforation was the only complication reported (7.6%) and it was surgically resolved. Conclusions: The feasibility and efficacy of ESD for the treatment of early gastric cancer was demonstrated at two healthcare centers in Lima, Peru. The complication rate was similar to that reported in the international medical literature. Palabras clave: Cáncer gástrico, Disección endoscópica submucosa, Keywords: Gastric cancer, Submucosal endoscopic dissection

Abstract The emergence of new hardware architectures, and the continuous production of data open new challenges for data management. It is no longer pertinent to reason with respect to a predefined set of resources (i.e., computing, storage and main memory). Instead, it is necessary to design data processing algorithms and processes considering unlimited resources via the “pay-as-you-go” model. According to this model, resources provision must consider the economic cost of the processes versus the use and parallel exploitation of available computing resources. In consequence, new methodologies, algorithms and tools for querying, deploying and programming data management functions have to be provided in scalable and elastic architectures that can cope with the characteristics of Big Data aware systems (intelligent systems, decision making, virtual environments, smart cities, drug personalization). These functions, must respect QoS properties (e.g., security, reliability, fault tolerance, dynamic evolution and adaptability) and behavior properties (e.g., transactional execution) according to application requirements. Mature and novel system architectures propose models and mechanisms for adding these properties to new efficient data management and processing functions delivered as services. This paper gives an overview of the different architectures in which efficient data management functions can be delivered for addressing Big Data processing challenges.

Background: Ulcerative colitis (UC) is a multifactorial and polygenic disease. Interleukin-22 (IL-22) is an immunomodulatory cytokine that belongs to the IL-10 family. Currently, some IL-22 polymorphisms have been associated with inflammatory processes such as rheumatoid arthritis and psoriasis vulgaris, but there are no studies on UC. Aim: The aim of this work was to study the frequency of polymorphisms of IL-22 in Mexican patients with UC. Methods: We studied a total of 199 Mexican patients with confirmed UC and 697 healthy controls. All individuals were born in Mexico, at least three family generations earlier. A blood sample was obtained from the UC patients and healthy controls in order to perform DNA extraction and then to determine the frequency of IL-22 polymorphisms (rs2227485, rs2272478, rs2227491). Results: No statistical significance was found in the gene and genotype frequencies of three SNPs of IL-22 (rs2227485, rs2272478, rs2227491) between the UC patients and healthy controls. No association was found between those IL-22 SNPs and clinical features of UC. Conclusions: There was no association between IL-22 SNPs (rs2227485, rs2272478, rs2227491) and the development of UC in a Mexican population.

Antecedentes: La colitis ulcerosa (CU) es una enfermedad multifactorial y poligénica. La interleucina (IL) 22 es una citocina inmunomoduladora que pertenece a la familia de IL-10. Actualmente, algunos polimorfismos de la IL-22 han sido asociados con procesos inflamatorios, como artritis reumatoide y psoriasis vulgar, sin embargo, no hay estudios en pacientes con CU. Objetivo: El objetivo del presente trabajo es estudiar la frecuencia de polimorfismos de la IL-22 en pacientes con CU. Métodos: Se estudió a 199 pacientes mexicanos con diagnóstico confirmado de CU y 697 controles sanos. Todos los individuos de estudio nacieron en México, al igual que sus últimas 3 generaciones. Se obtuvieron muestras de sangre de cada individuo y se extrajo ADN; finalmente, se determinó la frecuencia de polimorfismos en la IL-22 (rs2227485, rs2272478, rs2227491). Resultados: No se encontró diferencia significativa en la frecuencia del gen y genotipo de los SNP en la IL-22 (rs2227485, rs2272478, rs2227491) entre pacientes con CU y controles sanos. No se encontró asociación entre los SNP de la IL-22 y las características clínicas de la CU. Conclusiones: Ausencia de asociación entre los SNP de la IL-22 (rs2227485, rs2272478, rs2227491) y el desarrollo de CU en población mexicana.

La papa ( Solanum tuberosum) es una fuente de almidón importante que está subutilizada en el Perú, pues se importan principalmente los almidones de papa, pues no se ha logrado aún, que la industrialización de extracción de almidones sea un éxito. El presente trabajo tuvo como objetivo obtener, caracterizar y modificar, químicamente por acetilación, el almidón de una variedad comercial de papa, Única. La extracción se realizó con agua y la modificación química se realizó por acetilación mediante anhídrido acético a diferentes niveles (% v/w de almidón): 5, 10 y 15%. Se caracterizó el almidón nativo y almidón modificado: composición proximal, claridad, viscosidad aparente, estabilidad al congelamiento (sinéresis), y asimismo se midió el porcentaje de acetilación y el grado de sustitución. El rendimiento de extracción fue 16,5% y la viscosidad aparente del almidón nativo de papa fue 25000 mPa . s. Asimismo, se seleccionó el almidón acetilado con 15% de anhídrido acético para su aplicación en un helado crema debido a sus características funcionales. La viscosidad aparente del gel d e almidón AAc 15% fue 5429 mPa . s . El porcentaje de acetilación varió de 0,44 a 1,26% y el grado de sustitución no excedió los niveles recomendadas por FAO y JECFA. El almidón AAc 15% mostró el mejor perfil funcional para su aplicación como estabilizante y espesante en alimentos refrigerados.

Introducción: El dolor torácico no cardiaco (DTNC) se relaciona principalmente con enfermedades del esófago, y aunque se considera una condición común, en México la información aún es escasa. Objetivo: Evaluar las características clínicas y la calidad de vida relacionada con salud en pacientes con DTNC de presunto origen esofágico. Material y métodos: Se incluyeron en el estudio pacientes con DTNC de presunto origen esofágico, sin tratamiento previo. Se evaluaron los síntomas asociados, se realizó endoscopia alta y monitorización de pH esofágico de 24 h para establecer el diagnóstico de enfermedad por reflujo gastroesofágico, y para descartar trastornos en la motilidad esofágica se llevó a cabo manometría esofágica. Se aplicó el cuestionario de calidad de vida SF-36, y los resultados se compararon con un grupo control de sanos. Resultados: Se incluyeron 33 pacientes, el 61% mujeres, y la edad promedio fue 46.1 (± 11.6) años. Las causas de DTNC fueron: enfermedad por reflujo gastroesofágico 48%, acalasia 34% y dolor torácico funcional 18%. El tiempo promedio de progresión del dolor torácico fue 24 (2-240) meses, con ≤ 3 eventos/semana en el 52%. Los síntomas acompañantes más frecuentes fueron: regurgitaciones (81%), disfagia (72%) y pirosis (66%). Los pacientes con DTNC muestran deterioro en su calidad de vida comparado con el grupo control, independientemente de la etiología del dolor torácico. Los dominios más afectados son la percepción general de salud, problemas emocionales y la subescala de salud mental, sin diferencia estadística significativa (P > 0.05). Conclusiones: En nuestra población, los pacientes con DTNC muestran deterioro en su calidad de vida independientemente de la etiología, frecuencia y síntomas que acompañan al dolor torácico.

Introduction: Non-cardiac chest pain (NCCP) is mainly related to oesophageal disease, and in spite of being a common condition in Mexico, information regarding it is scarce. Aim: To assess the clinical characteristics and health-related quality of life of patients with NCCP of presumed oesophageal origin. Material and methods: Patients with NCCP of presumed oesophageal origin with no previous treatment were included in the study. Associated symptoms were assessed and upper gastrointestinal endoscopy and 24-hour oesophageal pH monitoring were performed to diagnose gastroesophageal reflux disease, while oesophageal manometry was used to determine oesophageal motility disorders. The SF-36 Health-Related Quality of Life (HR-QoL) questionnaire was completed and its results compared to a control group without oesophageal symptoms. Results: The study included 33 patients, of which 61% were women, and the mean age was 46.1 (± 11.6) years. Causes of NCCP were gastroesophageal reflux disease in 48%, achalasia in 34%, and functional chest pain in 18%. The average progression time for chest pain was 24 (2-240) months, with ≤3 events/week in 52% of the patients. The most frequent accompanying symptoms were: regurgitation (81%), dysphagia (72%) and heartburn (66%). Patients with NCCP show deterioration in HR-QoL compared to the control group (P = .01), regardless of chest pain aetiology. The most affected areas were general perception of health, emotional issues, and mental health sub-scale (P > 0.05). Conclusions: In our population, patients with NCCP show deterioration in HR-QoL regardless of the aetiology, frequency, and accompanying symptoms.

The crustal-scale west-vergent San Ramón thrust fault system, which lies at the foot of the main Andean Cordillera in central Chile, is a geologically active structure with manifestations of late Quaternary complex surface rupture on fault segments along the eastern border of the city of Santiago. From the comparison of geophysical and geological observations, we assessed the subsurface structural pattern that affects the sedimentary cover and rock-substratum topography across fault scarps, which is critical for evaluating structural models and associated seismic hazard along the related faults. We performed seismic profiles with an average length of 250 m, using an array of 24 geophones (Geode), with 25 shots per profile, to produce high-resolution seismic tomography to aid in interpreting impedance changes associated with the deformed sedimentary cover. The recorded travel-time refractions and reflections were jointly inverted by using a 2-D tomographic approach, which resulted in variations across the scarp axis in both the velocities and the reflections that are interpreted as the sedimentary cover-rock substratum topography. Seismic anisotropy observed from tomographic profiles is consistent with sediment deformation triggered by west-vergent thrust tectonics along the fault. Electrical soundings crossing two fault scarps were used to construct subsurface resistivity tomographic profiles, which reveal systematic differences between lower resistivity values in the hanging wall with respect to the footwall of the geological structure, and clearly show well-defined east-dipping resistivity boundaries. These boundaries can be interpreted in terms of structurally driven fluid content change between the hanging wall and the footwall of the San Ramón fault. The overall results are consistent with a west-vergent thrust structure dipping ~55° E in the subsurface beneath the piedmont sediments, with local complexities likely associated with variations in fault surface rupture propagation, fault splays and fault segment transfer zones.

Pulmonary lophomoniasis is a rare and life-threatening disease, most commonly reported across Asian and Latin American countries. Here, we have reported two cases of pulmonary lophomoniasis presenting with atypical manifestations. Case #1 represents a 19-year-old male patient with clinical characteristics suggestive of tuberculosis, presenting with hemoptysis and receiving antituberculosis treatment. Case #2 represents a 69-year-old man with post-tuberculosis pulmonary disease with cystic bronchiectasis presenting with polymicrobial co-infection. Based on our case experience, lophomoniasis should be considered in patients with pneumonia who do not respond to antibiotic treatment, and the corresponding epidemiological factors should be carefully considered in addition to bronchoscopy for precise diagnosis.

The Peru Chile Current ecosystem is characterized by high biological productivity and important fisheries. Although this system is likely to be severely affected by climate change, its response to current global warming is still uncertain. In this paper, we analyze 10–166 year-old sediments in two cores collected from Mejillones Bay, an anoxic sedimentary setting favorable for the preservation of proxies. Based on a 166-year chronology, we used proxies of bottom-water oxygenation (Mo, V, S, and the (lycopane + n−C35)/n−C31 ratio) and surface water productivity (biogenic opal, counts of diatom valves, biogenic Ba, organic carbon, and chlorins) to reconstruct environmental variations in Mejillones Bay. During the last two centuries, a shift took place in the coastal marine ecosystem of Bahia Mejillones at decadal scales. This shift was characterized by intense ENSO-like activity, large-scale fluctuations in biological export productivity and bottom water oxygenation, and increased eolian activity (inferred from Ti/Al and Zr/Al). This short-term variability was accompanied by a gradual increase of sulfidic conditions that has intensified since the early 1960s.

Climate and ocean ecosystem variability has been well recognized during the twentieth century but it is unclear if modern ocean biogeochemistry is susceptible to the large, abrupt shifts that characterized the Late Quaternary. Time series from marine sediments off Peru show an abrupt centennial-scale biogeochemical regime shift in the early nineteenth century, of much greater magnitude and duration than present day multi-decadal variability. A rapid expansion of the subsurface nutrient-rich, oxygen-depleted waters resulted in the present-day higher biological productivity, including pelagic fish. The shift was likely driven by a northward migration of the Intertropical Convergence Zone and the South Pacific Subtropical High to their present day locations, coupled with a strengthening of Walker circulation, towards the end of the Little Ice Age. These findings reveal the potential for large reorganizations in tropical Pacific climate with immediate effects on ocean biogeochemical cycling and ecosystem structure.

Se estudiaron formulaciones de materiales cerámicos ligados termoquímicamente empleando materias primas silicoaluminosas. Se prepararon mezclas con baja relación agua:sólidos y se procesaron mediante prensado hasta de 30 MPa. Las probetas se curaron a temperaturas de 200°C por 2 horas. Se evaluó la resistencia a la flexión después del tratamiento térmico; los valores registrados alcanzaron entre 6.9 y 15.7MPa, lo cual es superior a los cementos procesados por rutas convencionales. Las microestructuras obtenidas indicaron la formación de matrices densas, sugiriendo una respuesta favorable de las materias primas al proceso de activación. Las propiedades mecánicas variaron con la cantidad y tipo de materiales mezclados. La difracción de rayos X indicó que no hubo formación de fases zeolíticas y las fases cristalinas no reaccionaron durante el proceso de curado. El procesamiento propuesto es prometedor para obtener altas propiedades mecánicas en tiempos de curado cortos.

High-resolution paleo-environmental and paleo-ecological archives in laminated sequences are present in selected areas from the upper continental Peruvian margin within the oxygen minimum zone. We present initial results of a multidisciplinary study (the PALEOPECES project) that aims to reconstruct environmental and ecosystem variability during the past 200 years from high-resolution records. We report chronology development, sediment structure, elemental, organic, and mineralogical compositions of a box core collected at 300 m depth off Pisco, central Peru. An average sedimentation rate of 2.2 mm y-1 was estimated from downcore excess 210Pb activities for the last 100-150 years. Extending this rate further downcore indicates that a slump located at 52 cm depth from the top of the core can be correlated with a large tsunami that struck the coast of central Peru in 1746. X-ray analyses reveal laminated structures composed of couplets of light and dark laminae. Observations under polarized microscope show that light laminae are dominated by more dense, detrital and terrigenous material, while dark laminae are less dense with greater concentrations of amorphous biogenic silica. Downcore variations in dry bulk density and X-ray radioscopy of gray level show similar patterns, including a major shift at 34 cm depth (ca. mid-nineteenth century). A finely laminated sequence, which may include annual varves, is present between 34 cm depth and the slump layer. Sediment characteristics of the sequence suggest increased seasonality of terrigenous versus biogenous sedimentation during the corresponding period. In addition to a mid-nineteenth century change and considerable multidecadal variability in TOC, there is a positive trend in the past 50 years. Mineralogical analyses from a Fourier Transformed Infrared Spectroscopy (FTIR) of the upper core covering the last 25 years, indicate higher concentrations of the mineral fraction (quartz, feldspar, kaolinite and illite) in layers including large El Niño events (1982-1983, 1986-1987 and 1997-1998), with the largest peak during the 1997-1998 episode. These results confirm that anoxic sediments off Pisco are suitable archives to investigate interannual and decadal changes in oceanographic conditions and climate of the northern Humboldt upwelling system.

Chrysobalanus icaco se considera una especie que presenta diferencias morfológicas, el análisis del contenido de metabolitos secundarios de sus frutos podría ser una herramienta útil en su clasificación, la presencia de flavonoles y flavonas contribuyen a la quimiotaxonomía para determinar el parentesco de híbridos, así como para el reconocimiento y registro de nuevos cultivares. De esta forma, como un estudio preliminar se realizó una serie de análisis fitoquímicos por medio de cromatografía en papel descendente y espectrofotometría UV/VIS para obtener valores de Rf y espectrales que sirvan como base para identificar a los flavonoles y flavonas del fruto de C. icaco y además para estudios fitoquímicos posteriores. Los resultados preliminares indicaron la presencia del flavonol quercetina 3-arabinósido y de la flavona apigenina-7-O-glucósido.

A new species, Justicia darienensis T.F. Daniel & M. Vargas P., is described from a biodiverse "hotspot" in an isolated cloud forest of Darién Province in eastern Panama. It is compared to morphologically and palynologically similar species in southern Central America. Justicia darienensis is characterized by a complex inflorescence with heteromorphic (shape and fertility) bracts, white corollas with purple markings on the lower lip, glabrous anther thecae, 4-aperturate pollen, and pubescent capsules. Images of the plant and its pollen are provided. [ABSTRACT FROM AUTHOR]

Goblet cell metaplasia, a disabling hallmark of chronic lung disease, lacks curative treatments at present. To identify novel therapeutic targets for goblet cell metaplasia, we studied the transcriptional response profile of IL-13-exposed primary human airway epithelia in vitro and asthmatic airway epithelia in vivo. A perturbation-response profile connectivity approach identified geldanamycin, an inhibitor of heat shock protein 90 (HSP90) as a candidate therapeutic target. Our experiments confirmed that geldanamycin and other HSP90 inhibitors prevented IL-13-induced goblet cell metaplasia in vitro and in vivo. Geldanamycin also reverted established goblet cell metaplasia. Geldanamycin did not induce goblet cell death, nor did it solely block mucin synthesis or IL-13 receptor-proximal signaling. Geldanamycin affected the transcriptome of airway cells when exposed to IL-13, but not when exposed to vehicle. We hypothesized that the mechanism of action probably involves TGF-[beta], ERBB, or EHF, which would predict that geldanamycin would also revert IL-17-induced goblet cell metaplasia, a prediction confirmed by our experiments. Our findings suggest that persistent airway goblet cell metaplasia requires HSP90 activity and that HSP90 inhibitors will revert goblet cell metaplasia, despite active upstream inflammatory signaling. Moreover, HSP90 inhibitors may be a therapeutic option for airway diseases with goblet cell metaplasia of unknown mechanism., Introduction Human lungs constantly interact with the environment. In some individuals, various environmental exposures cause chronic mucus hypersecretion, leading to disability and reduced quality of life (1-3). Goblet cell metaplasia [...]